Commercial fishermen catch and process tons of fish a day. Many fishermen have complex, highly automated processing equipment that dresses the fish and produces numerous different commercial products for commercial retailers, such as restaurant chains or grocery stores. Such equipment is highly specialized to perform a specific task, such as cutting the heads and tails off, filleting, deboning and skinning, etc. One of the reasons such equipment must be tailored to specific tasks is the large variety of shapes and sizes of fish processed, including pollock, salmon, trout, sole, cod, etc.
To reduce overall processing costs and to improve quality, some commercial fishing vessels include processing equipment and freezers located directly on the ships. As the fish are caught, they are immediately processed and frozen, substantially improving the quality of the final product. This also allows the vessels to remain at sea for long periods of time without transporting the fish to a shore-based processing facility. Most of the processing equipment is large, complex, and expensive. It is difficult and expensive to remove the processing equipment from the vessel and replace it with new processing equipment.
Because of the expense associated with exchanging the processing equipment, including vessel down time, most commercial processing ships are intended to catch and process specific types of fish. As an example, the vessel may be fitted with processing equipment designed to process generally oval fish having a relatively thick cross section, such as pollock or salmon, or generally flat fish having a relatively thin cross section, such as sole. Due to the natural migration of fish, and various fishing laws, individual types of fish are caught and processed during limited times of the year. Therefore, vessels having equipment capable of processing only one type of fish sit idle during long periods of the year. If the processing equipment were available to process flat fish, such as sole, the vessels could be operated over a larger part of the year. This would, in turn, reduce the amount of down time and associated expense for the vessels.
One manufacturer of fish processing equipment is Baader GmbH & Co. KG, Lubeck, Germany ("Baader"). One of the many fish processing machines produced by Baader is the Baader 182. The Baader 182 is designed to process pollock and salmon-shaped fish and includes a conveyor having a plurality of fish holders mounted along the length of the conveyor. Each fish holder includes a recess configured to receive a pollock. While the processor is operating, a worker removes fish from a fish hopper located next to the conveyor and places an individual pollock in the recess of each fish holder. The conveyor subsequently moves the fish holders and pollock along the length of the conveyor into contact with rotating blades that cut both the head and the tail of the pollock off. The body of the pollock is then carried to additional equipment that cuts the pollock into fillets and removes the bones and skin.
The Baader 182 works well with fish having an oval cross section, such as pollock, but does not allow other types of fish to be processed. The Baader 182 is particularly unsuitable for processing fish with a relative flat cross section, such as sole. The fish holders used on the Baader 182 are not capable of holding such fish during processing. Nor can the Baader 182 remove the dorsal and anal fins of a flat fish.
In addition to having a relatively thin cross section, the body of a sole also has a smaller length to height ratio than pollock or salmon, i.e., the body of a sole is more oval-shaped when viewed from the side. The shape of the sole presents additional problems in processing. The orientation of the body of the sole must be carefully maintained to ensure that the head, tail, and dorsal and anal fins are removed in such a way as to leave the majority of the body intact. If the orientation of the sole is improper, the sole tends to be cut at angles that either remove too much of the body or leave parts of the head or tail. Therefore, it is important that the sole or similarly-shaped fish be carefully centered within the fish holders or belts before and/or while being brought into contact with the cutting knives.
Therefore, one goal of the present invention is to provide equipment to process flat fish, such as sole, to quickly and efficiently remove heads, tails, anal and dorsal fins, and internal organs. Another goal of the present invention is to allow processing equipment to center flat fish within the processing equipment and accurately cutting along outer body shapes while holding the fish, such that the head, tail fins, and organs, may be removed without costly losses of meat.
Additionally, the fish may be fed directly into other equipment to, for example, fillet and/or skin the sole or other flat fish. Another goal of the present invention is to speed the entire process such that fewer machines are actually required to accomplish the task and/or the time between catching and freezing the fish is shortened to provide an even fresher fish product.